Hey guys. Ive looked for what seemed like forever but couldn't find any info here yet. Here's my problem. I purchased a front D60 for an 79 F350/ did an arb and some new axles . and brakes. go for a road test and within 1 hour I heard a huge grinding noise. well long story short, the LF caliper was falling off. I had a new hardware kit in it too. checked some more and when I re-assembled everything. I tried to move the slider with a hammer and punch. with the locking bolt in place , I could still move the slider all the way to the inside. Until it falls out. I have a new bolt too. everything is new. I dont know what to do. I used to be a mechanic during this era and I never had this problem. My son , also a mechanic, said they have this problem as well with a newer F650. besides drilling a new hole to better hold the slider. is there anything else to try. the previous owner had redrilled the right side to 3/8 and used a reg bolt. so far seems to be good. If you remember correctly the original bolt has a taper under the head. . Im assuming that the cut outs on the sliders are supposed to be for the bolt. but my bolt body doesn't match with it. Oh I haven't tried a reg bolt to see it the head will hold the slider from going for another walk. anyone had something similar. or know of a reasonable fix?

 

Maybe you have the wrong bolt .... the bolts for my F-150 brake caliper slider "inserts" have a wide shoulder above the threaded portion to match that half moon shaped cut out.

Here is a pic of the F-350 parts.

http://www.rockauto.com/getimage/get...76-0&width=500

 

Thats the exact boly Im using. the cut out doesnt catch the cutout at all the bolt doesnt even contact the straight part . It just doesnt stop the slider from moving.

 

385194-S2 .. National Coarse Thread Bolt / 5/16" -18 x 1 1/8" long from shoulder to end.

1973/79 F100/250 2WD/4WD with single piston calipers / 1973/79 F250/350 2WD/4WD with dual piston calipers // 1976/79 Bronco // 1975/79 E100/150 / 1976/79 E250/350.

Shown as 385194-S in parts catalog pic. Notice 2B486 & 2B487: Originally, there were TWO different types for F250/350 4WD.

 

Well it sounds like you need to get the correct or at least a different bolt that will catch in the slider cut out. Also you should have tension from the spring tab #2B486.

Have you tried to match what the other side (that is working) has?

 

As stated above, do you have the flat spring in between the key and the bracket. I'm running the stock bolts on the same axle with no key walking issues. I used a little anti sieze on the bolts, and kept an eye on the bolts for about 2000 miles before it tore my truck down.

 

Everything is new. the cutout on the slider doesnt hold the bolt. The taper under the bolt head doesnt ever contact the slider. once its all bolted together I can still push the slider all the way out . with the bolt in place. Someone local said I need shims for the main bracket holding the calipers cause its worn out. I cant see that. that would have to be a lot of wear to happen like that not som ss shim. Im also told that some people weld a washer to the slider and then run the bolt through it. Im wondering if I can use a round spacer under the bolt head the increase in diam. going around the tapered portion. maybe the increase in dia. will help. Ive never had this ever in 30 some odd years. Oh the flat spring goes under the slider right?

 

Pictures are/would be helpful here. Sure you have correct slider.

 

I agree, I have 3 of those axles and all the bolts tapered surface is in direct contact with the slider so it can't move...something isn't right.

 

Are you sure you have part # 2B486 installed also? You should have to hammer/tap part #2B487 and part # 2b486 in the gap once the caliper is installed.

And then yes the bolt should contact the "slider" when installed.

 

This is how it goes together. Spring shim on top of key with ears down.
Make sure you put some anti sieze on the key and bolt threads so it comes apart next time.

 

You are missing part # 2B486, in Number Dummy's post. I have made that mistake and had your same results